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partial or generalised tonic-clonic seizures. Aggressive behaviour may occur and is usually
undirected or resistive and the patient is likely to be amnesic for the event.

Post-ictal mood disturbances include depression, anxiety or mania. Post-ictal depression can
last longer (up to two weeks) than other post-ictal states. Symptoms range from mild to severe
and may involve suicidal behaviour. It has been reported to occur more commonly with right-
sided temporal or frontal foci2. Post-ictal anxiety symptoms are less common. There are a few
case reports of post-ictal mania characterised by symptoms of overactivity, irritability, and
disorganised or disinhibited behaviour, which tend to be brief in duration.

Post-ictal psychosis
The prevalence has been estimated to be 610% in patients with epilepsy, particularly
temporal lobe epilepsy3. It typically occurs after a cluster of complex partial seizures (+/-
secondary generalisation). There is usually a period of lucidity (1272 hours) prior to the
onset of psychosis. The psychotic symptoms include delusions, hallucinations, thought
disorder or mania, which are usually transient but can last several weeks. It has also been
reported that some patients with recurrent episodes of post-ictal psychosis may develop an
inter-ictal psychosis4. Predisposing risk factors are ictal fear, bilateral epileptic foci or gross
structural lesions. Mechanisms are unknown but may be related to transient neurochemical
changes as a result of seizures, e.g. dopamine hypersensitivity or GABA-related mechanisms.

Treatment of acute post-ictal psychosis may require short courses of benzodiazepines or
antipsychotics. Improving seizure control would be the long-term goal.

Inter-ictal

Depression
Research has shown that nearly 40% of patients studied in tertiary epilepsy centres had major
depression and therefore it is the commonest psychiatric disorder seen in epilepsy5. The true
prevalence of depression in epileptic patients in the community has not been established. It
is reportedly more common in patients with temporal lobe epilepsy than in generalised
epilepsy. The clinical features of major depression include persistent low mood, anhedonia,
loss of interest and biological symptoms of sleep or appetite disturbance. However, it is
important to recognise that some patients can present with atypical depressive symptoms,
referred to as inter-ictal dysphoric disorder6. This is characterised by chronic intermittent
dysthymia, irritability and anxiety symptoms.

Treatment for depression includes psychological interventions such as counselling,
psychotherapy or cognitive/behaviour therapy if appropriate. For moderate to severe
depression, antidepressant medications can be prescribed. The potential risk of SSRIs
lowering seizure threshold is low (greater risk with tricyclics). Electroconvulsive treatment
can be effective for severe medication-resistant depression but there is a small risk of
increasing seizures.

Inter-ictal anxiety disorders
The incidence of inter-ictal anxiety disorders is greater than in the general population. Panic
disorder, generalised anxiety, agoraphobia, social phobia and obsessive compulsive disorder
(rare) can occur. They are reportedly more common in patients with temporal lobe epilepsy,
especially with left-sided foci. It is important to exclude other medical causes, e.g. thyroid,
endocrine, medication effects, etc. Psychosocial difficulties, social stigma and unpredictable
seizures may also contribute to anxiety symptoms.